Unfortunate thing on this is that there isn't a software update for the WebEx Meeting Player. TAC sent me over to WebEx support, and it looks like this vulnerability won't be addressed until T31.5.20, which might not be out for a couple weeks yet. The version available for download on https://www.webex.com/play-webex-recording.html is still T29.10.0.10115, which is vulnerable.